1. Field of the Invention
The present invention relates to a capacitive touch module, and more particularly to a capacitive touch module capable of generating three-dimensional (3D) images.
2. Description of the Related Art
Due to their slim shapes, low power dissipation and low radiation, liquid crystal displays (LCDs) are widely applied in mobile electronic devices such as notebooks, monitors, and smart-phones. Liquid crystal displays having touch input functions are also widely applied on more and more electronic devices as input interfaces. Touch displays include resistive type and capacitive type touch displays. Compared with the resistive type touch displays, the capacitive touch displays are capable of detecting multi-points touch inputs and can be operated in various ways. Besides, since 3D image applications are more and more popular, a display having both touch and 3D functions is needed.
Please refer to FIG. 1A, which shows a related art capacitive touch module 100 in a touch display. As shown in FIG. 1A, the capacitive touch module 100 includes a touch structure 110, a touch structure 110, a liquid crystal structure 120 and a processor 130. The touch structure 110 includes a plurality of receiving electrodes 112, a first insulating layer 22 and a plurality of transmission electrodes 114. The first insulating layer 22 is formed between the plurality of receiving electrodes 112 and the plurality of transmission electrodes 114. When driving pulses are received by the transmission electrodes 114, the plurality of receiving electrodes 112 will generate touch signals according to how the capacitive touch module 100 is being touched, and then transmit the touch signals to the processor 130 of the capacitive touch module 100.
The liquid crystal structure 120 includes a first glass layer 32, a second glass layer 34, a liquid crystal layer 50, a second insulating layer 24, a third insulating layer 26, a plurality of first transparent electrodes 122 and a plurality of second transparent electrodes. The liquid crystal layer 50 is disposed between the first glass layer 32 and the second glass layer 34. The second insulating layer 24 is formed between the first glass layer 32 and the liquid crystal layer 50. The third insulating layer 26 is formed between the liquid crystal layer 50 and the second glass layer 34. The first transparent electrodes 122 are formed between the second insulating layer 24 and the liquid crystal layer 50. The second transparent electrodes 124 are formed between the third insulating layer 26 and the second glass layer 34. The first transparent electrodes 122 and the second transparent electrodes are used to respectively receive pulse signals having the same phase or different phases, thus the touch display can generate 3D images or two-dimensional (2d) images accordingly.
However, in the capacitive touch module 100, because the distance between the touch structure 110 and the liquid crystal structure 120 is too short, and the signals of the touch structure 110 and the liquid crystal structure 120 are not synchronous, the driving signal of the touch structure 110 and the liquid crystal structure 120 do not match but interfere each other. Please refer to FIGS. 1B and 1C. FIG. 1B shows the timing of driving signal of the touch structure 110 in FIG. 1A, and FIG. 1C is a timing diagram showing the touch signals in FIG. 1B being affected by the driving signal of the liquid crystal structure 120 in FIG. 1A. In FIG. 1B, the driving signal of the touch structure 110 is not affected yet, but in FIG. 1C, the distance between the touch structure 110 and the liquid crystal structure 120 is too short, and the signals of the touch structure 110 and the liquid crystal structure 120 are not synchronous, thus the driving signal of the touch structure 110 is dramatically distorted by interference. This causes the capacitive touch module 100 to not detect touch inputs correctly. Besides, if taking both of the touch function and the 2D/3D images switching function into account, the capacitive touch module 100 will have larger thickness and heavier weights, thus can not meet the requirement that the weights of the displays should be lighter and lighter, and the thickness of the displays should be thinner and thinner.